1. Field of the Invention
This invention relates to teletypewriter machines and more specifically to such machines which can be used on a portable basis without external power.
2. Prior Art
Teletypewriter machines have been in widespread use for more than a quarter of a century. Generally, they have been large, heavy fixed machines located in business offices and used for national and international business transactions. They have served, more recently, as data input and output equipment for computers, i.e., as peripheral equipment.
In recent years there has been an increasing need for remote terminals for teletypewriter systems and for computer networks. The most recent entrants into the portable terminal field (to applicant's knowledge) are the machines manufactured by Micon Industries of Oakland, CA 94607. These machines weigh 6-14 pounds, cost approximately $1,000 and are intended primarily for computer I/O applications. To the best of applicant's knowledge the printer version of the Micon devices weighs 14 lbs. and is motor powered, which raises the machine's weight and power consumption. Further, it uses thermal printing which further increases power consumption and battery capacity requirements.
Attention is also directed to U.S. Pat. No. 3,493,091 (Kapp) which shows multiple solenoids used in shifting a printing head so that one of two type bands thereon is moved selectively, into an operative position. A stepping motor (of relatively high current consumption) is used for moving the printing drum.